CDP Table Error Entries

[Beginner]

Hey, 

I have a VLANs architecture where a switch has a separate VLAN with a core switch for inter-vlan routing.

All the switches are connected directly to the core switch and while having information about all the directly connected neighbors through show cdp neighbor command, i am getting error: 

Switch-4           Ten 1/0/4       143        S I        WS-C2960X       Gig 1/0/27
Switch-6           Ten 1/0/12     165        S I        WS-C2960X       Gig 1/0/27
Switch-3           Ten 1/0/8       168        S I        WS-C3650-        Ten 1/1/4
Switch-3           Ten 1/0/3       168        S I        WS-C3650-        Ten 1/1/4
Switch-2           Ten 1/0/8       178        S I        WS-C2960X       Gig 1/0/28
Switch-2           Ten 1/0/15     178        S I        WS-C2960X       Gig 1/0/28
Switch-1           Ten 1/0/8       176        S I        WS-C2960X       Gig 1/0/25

According to the output, there are two more switch's information coming on port Ten 1/0/8 whereas i have connected only switch-1 to that port, rest switches are connected to their respective ports directly. Also i have tested switch-1 connecting to the port other than 1/0/8 then cdp works fine i am getting this issue only with that particular port 1/0/8. Can anybody tell me that the port is having problem and if it is then what? 

[Julio E. Moisa]

Hi,

If you have the devices directly connected probably the holdtime is high, try modifying it or cleaning the cdp table. 

cdp holdtime <seconds>

clean cdp table

Other situation could be because the port is connected to Hub or configured as trunk. 

Hope it is useful

:-)

[Beginner]

Yeah, All ports are trunked but there is no hub in between switches also holdtime is also same on all switches, I am getting this problem only on a specific port and i tried clearing cdp counters, table and that port disable, enable everything. The problem still exist.

[Julio E. Moisa]

Hi,

Thank you, have you reloaded the switch? it could be a bug. What do you have at other end, any stack of switches? are they Cisco devices at the other end or other brand?

[Beginner]

Yeah, i have reloaded the switch, issue still exist

I have 3 switches connected directly on three different ports which are cisco switches. 

3650 is connected to port 1/0/3

2960 is connected to port 1/0/15

And 2960 is connected to port 1/0/8

I am getting the problem only when i connect one of them on port 1/0/8, while connecting with other ports of core switch, there is no such issue

[Larry Sullivan]

Wild guess here, but 1/0/8 isn't part of a port/etherchannel is it?  Also, what is output of show "cdp neighbor detail"?